Electric light fittings



May 25, 1965 B. STERN 3,135,837

ELECTRIC LIGHT FITTINGS Filed July 5, 1962 2 Sheets-Sheet 1 (AH/En! ToRBERN ARD TE? N mm+ mo y 5, 1965 B. STERN 3,185,837

ELECTRIC LIGHT FITTINGS Filed July 5, 1962 2 Sheets-Sheet 2 iii 2?BERNARD STERN United States Patent 3,185,837 ELECTRIC LIGHT FITTINGSBernard Stern, London, England, assignor to Rotafiex (Great Britain)Limited, London, England, a corporation of Great Britain Filed July 5,1962, Ser. No. 267,602 Qiaims. (Cl. 240-52) This invention relates toelectric light fittings and is designed to provide a new or improvedarrangement for supporting an electric lamp and which is adjustable tosuit various sizes and types of electric lamps. A further object is toprovide supporting means for the adjustable lamp fitting whereby thelatter can be turned to throw light from the lamp in various directions.

According to the invention, a support for an electric lamp holder ismounted within a tube adapted to enclose at least the stem of anelectric lamp, the lamp holder support being adjustable along the lengthof the tube to accommodate lamps of different lengths. The tube may bemounted in a bracket so as to be capable of swinging about a diametricalaxis of the tube, and if desired the bracket may be mounted on asupporting member and adapted for rotation about an axis at right anglesto the said diametrical axis. Conveniently, the lamp holder may becarried by a diametrical web in a member slidably mounted in the tube,the tube having two axially disposed slots diametrically opposite oneanother for engagement by studs on the member carrying the lamp holderto guide the said member and limit its movement relatively to the tube.

One particular construction will now be described by way of exampleonly, with reference to the accompanying drawings, in which:

FIGURE 1 is a perspective view of an electric lighting fittingconstructed according to the invention,

FIGURE 2 is a sectional elevation of the fitting shown in FIGURE 1, and

FIGURE 3 is detail sectional elevation of part of the fitting.

Referring to the drawings, the particular electric lighting fittingillustrated is intended for use with a spotlarnp of the kind in whichpart of the glass envelope of the lamp is silvered so as to serve as areflector. The fitting comprises a metal tube which has an end cap ordisc 11 at one end, the said end cap or disc 11 having a centralaperture 12 for the passage of flexible electric supply leads to theinterior of the tube 16. The open end of the tube will be referred to asthe front end and the end having the cap or disc 11 will be referred toas the rear end. A shorter tube 13 which is a sliding fit within thebore of the main tube It is disposed within the main tube and has anintegral diametrical wall 14 a short distance from the end of theshorter tube 13 nearest to the rear end of the main tube 10.

A rod 15 passes diametrically through the shorter tube 13 rearwardly oithe said Wall 14, the ends of the rod extending through axially disposedslots 16 in the main tube 10. The end portions of the rod 15 arescrewthreaded, but for convenience the rod 15 may be screwthreadedthroughout its entire length. A nut 17 is screwed on each end of the rod15, each nut having a cylindrical neck portion 18 adapted to passthrough a hole 19 in one limb of a substantially U-shaped bracket 26,and a washer or like spacing member 21 is fitted over each neck portion13 so as to lie between the inner surface of the corresponding limb ofthe bracket 20 and the outer surface of the main tube 10. When the nuts17 are tightened, the end faces of their neck portions will engage withthe main cylinder 10 adjacent to the slots 16 so as to clamp the shorteror inner tube 13 to the main tube 10, and at Cal the same time the limbsof the u shaped bracket 20 will be frictionally engaged between theWashers or spacing members 21 and the heads of the nuts 17.

The U-shaped bracket 2% in this particular construction comprises threesides of a rectangle whereby the central or base portion 22 issubstantially parallel with the rod 15 passing through the tubes. Thesaid central or base portion 22 of the bracket 20 may be adapted in anyconvenient manner for mounting the bracket on a support or forsuspending the bracket according to requirements. In this particularconstruction the bracket 20 is adapted to be mounted on one end of atubular conduit 23 through which electric supply leads extend. For thispurpose, a stop collar 24 is adapted to be screwed on to the end of theconduit 23, the outer end face of the stop collar having a peripheralcylindrical flange 25 defining a circular recess, and a blind hole 26being formed in the said outer end face. A saddle collar 27 is adaptedto fit in the said recess so as to project therefrom and a pin 28projecting from the inner face of the saddle collar 27 engages in thesaid blind hole 26 so as to prevent rotation of the saddle collarrelatively to the stop collar. The saddle collar 27 has a diametricallydisposed groove 29 in its outer face to accommodate the central portionof the base 22 of the bracket 20, and a tubular locking screw 30 havinga knurled head is passed through a hole in the centre or" the bracketbase 22, through the saddle collar 27 and into engagement with internalscrew-threads in the bore of the stop collar 24.

The diametrical wall 14 of the inner or shorter tube 13 has a centralhole 31 in which an electric lamp holder is to be mounted so that thelamp holder projects into the forward portion of the inner tube 13. Alamp holder socket is shown in dotted lines 32 in FIGURE 2. The electricsupply leads 33, see FIGURE 1, from the conduit are extended to passthrough the hole 12 in the rear end Wall 11 of the main tube 16 to thelamp holder mounted in the inner tube 13. The stem portion of anelectric lamp 34 can be inserted through the front end of the main tube10 and its cap engaged in the lamp holder. By loosening the nuts 17which clamp the inner and outer tubes 10 and 13 and also engage with thearms of the bracket 29, the inner tube 13 can be moved axially withinthe main tube 10 until the outer end of the main tube Ill lies close tothe rear of the electric lamp envelope or bulb as shown in FIGURE 1. Themain tube It) can be turned about an axis of the rod 15 to direct lightfrom the lamp as desired, and by tightening the nuts 17, the inner andmain tubes will be clamped together and the main tube will be secured inthe angular position to which it had been adjusted relatively to thebracket 20.

The main tube 10 serves as a neat housing for enclosing the lamp holderand the stem of the lamp, the adjustment of the inner tube and lampholder with the main tube enabling electric lamps of different sizes andtypes to be accommodated.

I claim:

1. An electric lighting fitting comprising a main tube to enclose atleast the stem portion of an electric lamp, an inner tube slidablewithinsaid main tube, a diametrical wall in said inner tube, said diametricalwall having an opening to receive an electric lamp holder, axiallydisposed slots in said main tube, radially outward projecting screwedstuds on said inner tube, said studs extending slidably through saidslots in said main tube, a U-shaped bracket embracing said main tube,said screwed studs extending through holes in the arms of said U-shapedbracket, and nuts on the outer ends of said screwed studs for lockingthe inner tube in an axially adjusted position along the main tube andlocking the main tube in angularly adjusted position upon said U-shapedbracket.

2. An electric lamp mounting assembly comprising a main tube havingopposed wall slots, a bracket having spaced arms one on each side ofsaid main tube, said arms having apertures aligned with said slots, alamp support member mounted for axial adjustment Within said main tubeand comprising oppositely extending fixed projections extending slidablythrough said slots and rotatably into said bracket arm apertures, andfastener means on said projections adapted to be tightened to securesaid support member in an axially adjusted positionalong said main tubeand said main tube in a desired angular location on said bracket.

3. In the electric lamp mounting assembly defined in claim 2, said lampsupport member comprising a support tube telescoped within the main tubeand having a transverse wall in which is mounted a lamp socket, anelectric conduit connection secured to said bracket, and flexibleconductor leads extending between said conduit connection and saidsocket.

4. In the electric lamp mounting assembly defined in claim 2, saidprojections having threaded outer ends, spacers surrounding saidprojections between the bracket arms and said main tube, and saidfastener means comprising nuts on said threaded projection ends havingreduced sections extending through said apertures and said spacers intocontact with said main tube whereby tightening of said nuts :draws saidbracket arms and lamp support members toward each other with the maintube clamped therebetween.

5. In the electric lamp mounting assembly defined in claim 2, saidbracket having a bridge connecting said arms, an electric conduit endconnection extending through and clamped to said bridge, and flexiblewires extending from saidconduit end connection to a lamp socket on saidsupport member.

References (Iited by the Examiner ,7 UNKTED STATES PATENTS 1,493,487

NORTON ANSI-1BR, Primary Examiner.

LAWRENCE CHARLES, Examiner.

1. AN ELECTRIC LIGHTING FITTING COMPRISING A MAIN TUBE TO ENCLOSE ATLEAST THE STEM PORTION OF AN ELECTRIC LAMP, AN INNER TUBE SLIDABLEWITHIN SAID MAIN TUBE, A DIAMETRICAL WALL IN SAID INNER TUBE, SAID MAINTUBE, A DIAMETRICAL OPENING TO RECEIVE AN ELECTRIC LAMP HOLDER, AXIALLYDISPOSED SLOTS IN SAID MAIN TUBE, RADIALLY OUTWARD PROJECTING SCREWEDSTUDS ON SAID INNER TUBE, SAID STUDS EXTENDING SLIDABLY THROUGH SAIDSLOTS IN SAID MAIN TUBE, A U-SHAPED BRACKET EMBRACING SAID MAIN TUBE,SAID SCREWED STUDS EXTENDING THROUGH HOLES IN THE ARMS OF SAID U-SHAPEDBRACKET, AND NUTS ON THE OUTER ENDS OF SAID SCREWED STUDS FOR LOCKINGTHE INNER TUBE IN AN AXIALLY ADJUSTED POSITION ALONG THE MAIN TUBE ANDLOCKING THE MAIN TUBE IN ANGULARLY ADJUSTED POSITION UPON SAID U-SHAPEDBRACKET.